Method of making aperture cards



LANGAN ETAL 3,212,412

METHOD OF MAKING APEHTURE' CARDS Original Filed April 30, 1962 Oct. 19,1965 2 Sheets-Sheet 1 INVENTORS JOHN F. LANGAN LORLMER CLAYTON, JR.

GRANT E. ALLEN ,JR.

BY 2 W fimmnfi mw ATTORNEYS UFW JUNE; .MD 104 mm UZH QZHNTO UnitedStates Patent Office 3 ,212,412- Patented Oct. 19, 1965 9 Claims. (Cl.93--1) This application is a division of prior application, Serial No.191,117, filed April 30, 1962 for Aperture Cards.

This invention relates to improvements in cards adapted for mountingprojectable transparencies such as for example film record cards inwhich individual microfilm sections are mounted to facilitate thehandling, filing and storage of the transparencies, and also the sortingout, projecting and if desired the reproducing of individualtransparencies when desired. The invention relates especially to novelblank cards adapted for such uses and to their manufacture.

The invention is particularly useful in mounting microfilm sections incards that are capable of being sorted mechanically, although it is notlimited to this use as explained hereinafter. Various types ofmechanical sorting systems are well known. They range from systems inwhich groups of related cards can be separated and extracted from astack by inserting a pin or like instru ment through aligned holes inthe edges of the cards, to the elaborate and well known IBM system inwhich the cards are perforated according to a code and are sorted byelectrically controlled apparatus responsive to the location of theperforations in the individual cards. However, the invention alsocomprehends the mounting of projectionable transparencies, including alltypes of photographic film records, in ordinary file cards, catalogcards, and the like.

With reference to machine sorting of the IBM type, the present inventioncomprises important improvements of the punch cards or aperture cardsdisclosed in the priod Langan Patents Nos. 2,511,859, 2,512,106, and2,587,022, as well as in the preparation and use of such cards. Aperturecards of the type shown in these prior patents have been very widelyused, especially by the United States Government. By way of example, acurrent program of standardization of the preparation and distributionof engineering data by this system, such as drawings, specifications andthe like, in one particular Government field is estimated to require 90million aperture cards initially and average annual usage thereafter ofmillion aperture cards.

The merit of such aperture card systems is attested by their widespreadadoption and successful use, in spite of serious defects of priorsystems which are corrected by the present invention. One such defecthas had to do with the blank cards as supplied heretofore in bulkquantity to the ultimate user, i.e., before the film is mounted therein.As disclosed in the prior Langan Patent No. 2,511,859 mentioned above,these blank cards are distributed with the aperture already formed andwith a strip of pressure-sensitive adhesive material secured to thebackside of the card around the edges of the aperture, a narrow sectionof this strip extending into the aperture with exposed adhesive thereonfor subsequent mounting of a transparency in the aperture. This exposedadhesive is covered by a temporary sheet of glassine paper or similarmaterial.

In the first place, such blank cards cannot ordinarily be furnished to aprospective user in large supply because they must be used within arelatively short period or else the adhesive deteriorates to the pointwhere adequate bonding of the transparency cannot be secured. In largepart because of this inability to store reserve supplies of blank cards,the common practice has been for the customer to send his microfilm to acentral service center where the individual film sections are mounted inthe cards. The fact that the customer cannot cut out and mount sectionshimself, as and when desired, has heretofore made for inflexibility inthe use of the aperture cards and has detracted seriously from theutility and desirability of aperture card systems.

The factor mentioned above also makes it practically impossible to useaperture cards for mounting two or more sequential transparencies on thesame card, as is often desirable in order to post a record of successivestages of development of a project. In such cases, it iS desirable tomount the first transparency in one aperture of a card, and to be ableto upplement the original record by mounting a second transparency atsome later date in a second aperture of the same card. Using cards ofthe type heretofore used, however, when the time came for mounting thesecond transparency, the pressuresensitive adhesive material around thesecond aperture would no longer be effective so that a separate cardwould have to be used.

Another problem arises from frequent sticking together of adjacent cardsdue either to exposed pressure-sensitive adhesive in the case ofimperfect preparation, or to bleeding of the pressure-sensitive adhesivematerial from underneath the edges of the protective glassine coversheet or the edges of the transparency itself. In such cases theseparation of blank cards for perforation according to a mechanicalsorting code, or for the operations of mounting sections of filmtherein, or during subsequent use of the finished cards for machinesorting, projection, and the like, is hindered to an extent whichmilitates seriously against the usefulness of such systems.

Furthermore, any increase in thickness of such cards is veryundesirable. Even though an applied strip of adhesive may only increasethe thickness of a card by an extremely small amount, say ,1 of an inch,still when a deck of 1000 or more cards are stacked in a file drawer asis often the case, there will be a difference of an inch or more in thelength of one side of the stack as compared with the other.

Still further objections to prior systems arise from the fact that theoperations involved in preparing the blank cards, i.e., punching out theapertures and then'applying the adhesive strips and the cover sheets, aswell as the operations involved in finishing the cards includingstripping off the cover sheets and disposing of them and then applyingthe transparencies to the exposed adhesive strips, both requireobjectionably elaborate and expensive apparatus such as illustrated forexample in the prior Standish Patent No. 2,666,543, the prior MorrisonPatents Nos.,2,493,159 and 2,560,301, and the prior Baker Patent No.2,643,786. Many users of aperture cards have only a relatively smallnumber of transparencies to be mounted at one time, and this onlysporadically, so that they cannot justify the expense of purchasing andmaintaining such elaborate equipment but must again rely on servicecenters such as mentioned above.

But perhaps a more basic objection is that the bond between thetransparency and the card is not secure enough in many cases. Forexample, under ordinary conditions of usage, a deck comprising say 1000cards bearing microfilmed engineering drawings should last for yearsdespite repeated handling incident to removing the card from andreturning them to the drawer, riflling decks of cards before placingthem in sorting machines, handling individual cards in projectionmachines, print copiers, and the like, etc. In the course of suchmanipulations, the cards are repeatedly subjected to twisting andbending from all angles. Unless the bond between the film section andthe card is continuous, strong, and permanent, separation of the filmfrom the adhesive may eventually occur with the result that the cardmust be thrown away and the film section re-mounted in a fresh blankcard.

Added to the above disadvantages is the fact that even though theaperture in the blank card is covered by a temporary removable coversheet, still the presence of the aperture is undesirable for variousreasons. It obviously detracts from the mechanical strength of the blankcard, and it may interfere with and hinder the perforation of the cardfor mechanical sorting before the transparency is mounted.

Various attempts have been made to eliminate the use of suchpressure-sensitive adhesives and to remedy the defects mentioned. By wayof example, the prior Langan Patent No. 2,587,022 suggests heat bondingof thermoplastic materials to the card, proposing to cover the aperturewith a sheet of cellulose acetate and to bond its edges by heat andpressure to the edges of the card around the aperture. The material ofthis cover sheet was proposed to be the same as or similar to that ofthe base of the film itself, with the thought that subsequently the filmsection and the cover sheet could be united integrally by heat andpressure to form a unitary transparency across the aperture. Usuallyheat damage to the film resulted, however, such as clouding and/ orbuckling or Warping of the film. Moreover, the bond formed by heatingthe cellulose acetate cover sheet and pressing it into contact with thecard, or by doing the same thing to the edges of the cellulose acetatebase of the film itself as suggested in the prior Langan Patent No.2,633,655, was unsatisfactory. If the degree of heat was only enough tosoften the cellulose acetate it would not penetrate the fibers of thecard and the bond was weak and unsatisfactory. Attempts to increasefluidity by raising the temperature usually caused warping or bucklingof the card itself.

A step toward the elimination of the above ditficulties has beendisclosed and claimed in the copending application of John F. Langan,Serial No. 70,814 filed November 21, 1960, now US. Patent No. 3,165,804,issued Jan. 19, 1965, and entitled Aperture Card System. As disclosed inthis prior application, the strength of the eventual bond between thefilm and the card is materially increased by applying a solution ofthermoplastic material to the card so that it soaks into the cardfibers. Accordingly when the solvent dries out, the thermoplastic soluteis left not only on the surface of the card but also beneath its surfaceand distributed on and among the fibers of the card structure. Then whenthe bond is ultimately formed, this thermoplastic material and thethermoplastic film base as well are softened by heat so as to becometacky and merge or weld together under pressure to join the film to thecard with a bond strength that is much higher than can be obtained bymere surface adhesion. It has been found, however, that the heatrequired to secure effective Welding and that warping or other damage tothe card usually results.

As will be explained hereinafter, the present invention involves to someextent an impregnation of the card fibers with bonding, materialaccording to the aforesaid prior application Serial No. 70,814. However,one of its important advantages is that substantially less heat isrequired for bonding. Accordingly the bonding material should be onethat is dry and non-sticky or non-tacky at ordinary temperatures and upto say 200 F., since business machine mechanisms often developtemperatures around 150 F. or more as the result of sustained operation.However, in order to avoid using too high temperatures during thebondings of the film section on the card, the bonding material should beheat activatable at a temperature in the range of 250 F. to 350 F.Usuall it. is preferred to employ blends of commercially availableelastomeric and resinous products in suitable solvents such as methylethyl ketone, isobutyl ketone, acetone, and the like or in the form offast drying emulsions. The commercially available normally liquidadhesive known as Pliobond gives very satisfactory results. In fact,this material can be activated without heat by the addition of a smallamount of solvent.

As in the prior application mentioned above, the zone of application ofthe solution to the card must be such that the bonding material will belocated around the edges of the aperture, when it is eventually cut out.Of course, this can be accomplished by applying the solution over theentire area of the aperture, or for that matter over the entire area ofthe card when it is manufactured, but it is more economical to apply thesolution in a strip pattern following the outline of the aperture to becut out, or of the several apertures to be cut out, as the case may be.

The solution can be applied in the desired strip pattern or patterns byhand by simply brushing it on the surface of the card, but usuallysuitable mechanical applicator means will be preferred. For example, thecards may be moved in succession through a zone in which the desiredstrip pattern application is effected by relative movement between theindividual cards and suitable applicators. A reciprocable stampingdevice with a suitable inker can be used, or the cards may be fed insuccession through rotary printing devices; in either case the solution,colored or not, provides the ink with which the card is printed in thedesired pattern.

Thus cards embodying the present invention, before the film is mountedtherein, provide the very substantial advantages over the prior artmentioned above with regard to storage, distribution, etc. However, thepresent invention provides further advantages of major importancebecause it is not necessary to heat-soften the edges of the film sectionand then to compress them together with the card to thin the edges byplastic flow and to force the film down into the aperture, as disclosedfor example in prior Langan Patent No. 2,633,655 mentioned above.

The first step in the present invention is to indent one side of thecard around the outline of the aperture eventually to be cut therein, soas to form a trench-like de pression in one face of the card and acorresponding ridgelike projection embossed on the opposite surface ofthe card. It will be apparent that this stamping or embossing operationcan be performed by any suitable type of reciprocating or rotating diemechanism. While it has been proposed heretofore to pre-dimple suchcards by compressing the edges of the aperture, as for example in theprior Patent No. 2,633,655, the extent of such dimpling that can beproduced merely by compression, Without embossing the opposite side ofthe card, is limited by the compressibility of the card material and asa practical matter a depression of say 0.0010.002 inch is about themaximum that can be realized with the usual card having an initialthickness of approximately 0.0067 inch. Such depressions are not ofsufficient depth to accommodate the thickness of the film (varying fromabout 0.003 to about 0.0055 inch) and accordingly a very large amount ofthinning of the margins of the film by plastic flow and deformation isrequired in order to approach the desired final condition illustrated insaid prior patent. According to the present invention, on the otherhand, grooving or indentation of the card on one side can easily be mademuch deeper by permitting the card to be embossed on the other side, thestamping or embossing operation producing a sort of bending or foldingof the card material instead of compression thereof.

The next step according to the present invention is to remove theridge-like embossed projection from the opposite surface of the card inany suitable manner so as to restore the surface on this side of thecard to a planar condition. This can be accomplished by any suitablecutting or shaving operation, but most conveniently by high speedgrinding or abrasion applied to the cards while moving relatively pastthe grinding device. This produces a card which is substantially planarover one side, and is planar on the other side as well except thataround the outline of the aperture eventually to be cut out, there is atrench-like depression the bottom of which is formed by a thin web ofcard material. When the portion of the card surrounded by this trench iseventually cut out to form the aperture, the combined thickness of thefilm-and of the ledge around the aperture (which ledge previously formedthe bottom of the groove) is not materially, if any, more than thethickness of the card. By way of example, a card initially 0.0067 inchthick may be embossed and ground to a web thickness of about 0.015-0.002 inch in the bottom of the trench around the aperture and the addedthickness of the usual silver halide film of say 0.0055 inch makes atotal of around 0.007 inch.

It will be understood that the depth to which the blank cards arestamped or embossed, and the corresponding thickness of the cardmaterial at the bottom of the groove may vary depending upon the kind offilm to be mounted, the web being for example from about 0.004 inch toabout 0.002 inch or less for film varying in thickness within the rangestated above. Nevertheless the strength of such thin sections necessaryfor handling the cards is provided by the thermoplastic bondingmaterial. In the case of cards impregnated throughout in the course ofmanufacture, the thermoplastic material will already be present in thecard fibers of the thinned sections before and during the embossing andgrinding operations. In other cases where it is preferred to apply thebonding material.

in a strip pattern around the outline of the aperture, a solutionthereof can be applied by hand or preferably by mechanical means such asa suitable rotating inking member and a cooperating fountain or othersupply of solution, and as this solution dries, the thermoplasticbonding material remains to provide the strengthening effect alreadymentioned. An additional advantage of the present invention is thatbecause the card surface in the area to which bonding material isapplied has been roughened and de-sized by the grinding operation, withthe result that the solution quickly penetrates into the fibrous cardstructure and dries to leave the thermoplastic bonding material not onlycoated over the ground surfaces but also extending into the fibrousstructure of the web, often throughout its entire thickness.

*It has been proposed heretofore to remove material from one surface ofa card by means of grinding or milling so as to thin the card throughouta predetermined area intended to receive a laminar insert such as a film(see for example British Patent No. 886,852). Such cards areunsatisfactory, however, because the very thin web of card materialremaining over the entire area of the eventual aperture is not strongenough to meet the conditions of use of aperture cards while still inblank condition, i.e., without having film inserts mounted thereon forindefinite periods. On the other hand, it is impracticable to employ agrinding or milling tool following the narrow rectangular pathcharacteristic of the present invention relative to each individualcard. These deficiencies of cards such as disclosed in the Britishpatent are avoided by the method of the present invention in whichmaterial is removed from the card only over the aforesaid narrowrectangular path. Because of the embossing, the grinding or millingeffect is limited to this area while at the same time the desiredremoval of the raised or embossed material is accomplished byunidirectional movement of the card past the grinding or milling tool ina single pass. During such grinding or milling, it is important tosupport the embomed area against the pressure of the tool to prevent thecard material from being flattened out again with consequent spreadingof the effect of the tool beyond the desired limits and/or failure toaccomplish the desired removal. Therefore the card should be left on theembossing die, or placed on a similar die-like support, while removal ofthe card material is taking place. Preferably this die or support forthe bottom of the embossed groove should be high enough so that therewill be space or clearance during grinding for card areas beyond the topsurface of the Support to depress or fall away from the tool and thuslimit its effect to an area corresponding closely in shape and extentwith said top surfaces.

Except in the case of pre-impregnated card materials, blank cardsembodying the present invention are completed by the application of thesolution of bonding materials as already described, preferably to theareas from which embossed material has been removed. For mos-t purposesit is desirable to apply the solution in sufficient quantity to leave afilm of solid thermoplastic bonding material on the web surfaces, say0.0003 inch to 0.0005 inch thick. The blank cards are then ready forstorage, sale and/or use for the purposes and with the advantagesalready explained.

When it comes to mounting the transparency in a blank card of the abovetype, the transparency is prepared in any suitable way. For example, itmay require edge trimming to the desired shape and size which obviouslycan be done by hand if desired. In cutting out transparencies from aroll of film or the like, however, suitable die-cutting apparatus,either hand or power operated, will usually be preferred. It will beunderstood that the film size should be limited so that it overlaps thethin web surrounding the aperture but not the thicker surrounding card.

The same type of die-cutting operation is preferred for cutting out theapertures in the cards. With the aid of suitable registering means, thecards can be fed one by one to a die in position that such operation ofthe die cuts the aperture with its edges lying in the thinned web ofcard material to which the bonding material has been applied. Anydesired type of feeding mechanism can be used, or the cards can be fedby hand. -For most purposes a simple reciprocating die is satisfactory;it can be operated by hand or foot or by any desired power means.

The actual bonding operation may not require heat if provision is madefor activation of the bonding material by solvent addition. However,mild heat in the range of 250350 F., can also be employed for activationof the bonding material, but without substantial softening of the filmitself. For this purpose it is preferred to employ a hot die having therectangular shape and size of the perimeter of the aperture and a hotsurface approximately /s" wide. Preferably this hot surface is broughtin contact with the web on the side opposite to that to which the filmis applied. The heat passes quickly through the thin web and softens thethermoplastic bonding material next to the film, the rapid heat transferdue to the thin web enabling the use of lower temperatures and/orshorter times. Simultaneous pressure is applied to squeeze the web andfilm together. The amount of pressure is not critical and can varywidely, say in the range of p.s.i. to 1000 p.s.i. Under these conditionsplastic flow of the activated bonding material can take place in formingthe bond, but no plastic deformation of the film itself occurs.

One embodiment of the invention has been illustrated diagrammatically inthe accompanying drawings, but it is to be expressly understood thatsaid drawings are for purposes of illustration only and are not to betaken as a definition of the limits of the invention, reference beinghad to the appended claims for this purpose.

In the drawings,

FIG. 1 is a diagrammatic illustration of the sequence of steps involvedin preparing blank cards embodying the present invention in automatedmanner;

FIG. la is a view of an embossing die;

FIG. 2 is a plan view of one of the finished blank cards;

FIG. 3 is a section on the line 33 of FIG. 2;

FIGS. 4 and are sectional views corresponding to FIG. 3 but showingsubsequent successive steps in the completion of the blank cards;

FIG. 6 illustrates diagrammatically the step of cutting out the aperturein a blank card;

'FIG. 7 shows the operation of bonding a section of film in place on thecard; and

FIG. 8 shows the completed card with the film mounted therein. 7

Referring first to FIG. 1, a stack of cards to be processed is indicatedby the numeral 1 at the left hand side of the figure. For example, thesecards may be punch cards of the usual type employed with the IBM systemof tabulating card machines, being formed of card stock having aspecified thickness of 0.0067 inch with a tolerance of plus or minus0.0004 inch. As will be understood, the stack of cards can be supportedin any suitable magazine from which the cards are fed one by one insuccession from the bottom of the stack in the direction indicated bythe arrow 2, such feeding mechanisms being well known in the art.

As already stated, the first step according to the present inventioncomprises an embossing or stamping operation. When the cards are to beprinted, this embossing operation can be combined with the printingpress if desired so that the printed cards leave the press in embossedcondition, but as here shown for purposes of illustration, the embossingoperation is performed by passing the cards longitudinally in successionbetween the upper embossing roller 3 and a lower backing roller 4 ofrubber or the like. One of the cards is shown at 5 as it passes betweenthese rollers and is embossed in the desired pattern by means of dies 6carried by the roller 3 at peripheral intervals corresponding with therate of feed of cards 5.

A detailed diagrammatic view of one of these embossing dies is shown inFIG. 1A. It comprises raised ribs 7 extending circumferentially of theroller 3 and parallel to but spaced from one another, the ends of theseribs being cross-connected by transverse ribs 8 so that the ribstogether form a rectangular outline to be embossed on the card 5. Ofcourse, other shapes may be desirable. The height of the ribs 7 and 8will obviously be predetermined so as to produce embossing of thedesired depth, depending upon the thickness of the film to be mountedand to some extent also on the yieldabili-ty of the rubber backingroller 4. It will be evident that a similar die arrangement can beprovided on a conventional reciprocating stamping die.

Having been embossed, the cards pass from the rollers 3, 4 to a secondset of rollers 9 and 10 which accomplish the operation of removing theembossed ridges from the back of the card as described above. In orderto provide the desired support against the pressure of the operativelower wheel 10, the upper wheel 9 carries a series of die-like supports11 similar in size and shape to the dies 6 of the roller 3. The grindingwheel, by way of example, may be an aluminum oxide wheel running at asurface or linear peripheral speed of approximately 2300 feet perminute, having a wheel grit size of 46-60 and Wheel hardness in therange of G to J (the letters at the beginning of the alphabet indicatingsofter grades). Of course, these values are not critical; for example,the linear peripheral speed of the grinding wheel may vary betweenapproximate limits of 1800 feet per minute and 3000 feet per minute.

Referring to FIG. 3, the depth of embossing by the dies 6 may beapproximately 0.0045 inch, in the case of relatively thick film such asthe usual silver halide film which approximates 0.0055 inch. In such acase, the height of the ribs forming the dies 6 at supports 11 should besomewhat higher, say in the range of 0.006 inch to 0.01 inch. In passingbetween the rollers 9 and 10, therefore, the embossed ridges are removedfrom the back of the card as explained above, converting it from thecondition shown in FIG. 3 to that shown in FIG. 4 and leaving a webthickness of about 0.002 inch.

For the purpose of applying the solution of thermoplastic bondingmaterial, any suitable printing device can be employed. As illustrateddiagrammatically in FIG. 1, the cards 5 pass in succession between abacking roll 12 and a printing roller 13 having on its surface suitablesolutionaapplying means 14 such as a pad or wick arranged in a patternto correspond with the pattern or embossing and grinding previouslyperformed. Any known type of solution supply can be employed, and forpurposes of illustration FIG. 1 shows an inking roller 15 which rotatespartially submerged in a bath 16 of the desired solution and transfersthe solution to the applicator means 14.

Following the application of the bonding solution, which dries rapidly(this can be hastened by conventional means such as hot air blasts,infra-red radiation or the like), the cards 5 pass to any suitablereceptacle here shown as a stack 17.

FIG. 3, as already noted, shows the condition of the blank cards afterhaving passed between rollers 3 and 4. During this passage, die members6 create an indented groove 18 on one side of the card and acorresponding ridge-like projection 19 on the other side. As will beunderstood from the foregoing general description, the groove 18 may beapproximately inch Wide and follows the rectangular outline of theaperture eventually to be cut in the card.

The card 5 next passes between the wheels 9 and 10, where its conditionprogresses to that shown in FIG. 4 wherein the ridge-like projections 19of FIG. 3 have been ground away, leaving the thin webs 20 forming thebottom of said grooves and connecting the surrounding major H portion ofthe card indicated at 21 with the rectangular section 22 which iseventually to be removed to form the aperture. As already pointed out,these webs 20 may be as little as 0.0015 inch to 0.002 inch, and whilethey are quite narrow (usually 0.125 inch), nevertheless in thecondition shown in FIG. 4 they are too weak for safety in storage,distribution and handling of such cards before the film is actuallyinserted therein. Application of the solution of thermoplastic bondingmaterial by the roller 13, however, results in some impregnation of thewebs 20, as indicated by the stippling in FIG. 5, and also in buildingup a relatively thin but substantially continuous externallayer of solidthermoplastic bonding material indicated at 23. As a result, theinherently weak thin webs 20 are substantially strengthened to withstandall normal conditions of use of the blank cards, including not onlymanual handling but often the punching of said cards by machineaccording to desired machine sorting codes, etc. At the same time thesewebs are pushed in by the applicators 14 as shown in FIG. 5.

When it comes to mounting the desired section of film in a card of thetype described, the first operation is to die out the aperture asindicated diagrammatically in FIG. 6 in which a suitable punch 24punches out the section 22 through an opening in the base 25 by whichthe card 5 is supported. As shown, the dimensions of the opening of thebase and of the punch are such that the cut is made through the thinwebs 20 around the section 22, leaving the major portions of these websprojecting into the aperture. Having thus formed the aperture, thedesired section of film is then brought to the position shown in FIG. 7.Here the card 5 rests on a supporting table 26 comprising a heatedsupport 27 which has substantially the same size and shape as theportions of the webs 20 which project into the aperture and overlap theedges of the film section. The central part of this support 27 ispreferably left hollow or empty. Heat may be supplied to the support 27in any desired way, as by conventional electrical heating coils 28 whichmaintain the surfaces of the support at a temperature of say 300 F. Thefilm section can be applied either to the front or back of the card, butpreferably is in direct contact with the coating 23 of bonding materialwhich is preferably applied to the ground areas of the back of the cardas already stated. This preferred arrangement is shown in FIG. 7,wherein the film, comprising the usual base 29 coated with the usualemulsion 30, is positioned with its edges overlapping the coated andimpregnated webs 20. Pressure is then applied by means of any suitablepressure plate 31, simultaneously with the softening of the bondingmaterial by heat supplied through the support 27. The result is that thewebs 20 and the film itself are forced downwardly in the aperture in thecard to a position substantially as indicated in FIG. 8 in which theouter surface of the emulsion side 30 of the film is substantially flushwith the upper surface of the card, whereas the outer surface of thebase 29 of the film is bonded to the underlying webs 20 and issubstantially flush with the lower surface of the card In theillustration given above, the total thickness of the web (say 0.0015")and of the film (about 0.0055") is 0.007 inch which is within theprescribed tolerance limits of card thickness.

While only one embodiment of the invention has been specificallydescribed and illustrated, it is to be understood that the invention isnot restricted to this embodiment and that reference should be had tothe appended claims for a definition of the limits of the invention.

What is claimed is:

1. A method of making record cards of fibrous ma terial adapted to beapertured at predetermined locations for projectably mounting sectionsof microfilm and like projectable transparencies, comprising the stepsof embossing the card by indicating one side thereof to form a narrowelongated trench-like area which extends around the outline of anaperture to be formed, thereby forming a corresponding projecting areaon the other side of the card, and then supporting said indented areawhile removing the projecting material from said other side of said cardto a predetermined thickness over said supported area, the remainingcard area being unsupported outside said indented area and beingdepressible below the level of said support whereby removal of cardmaterial is limited substantially to said supported area.

2. A method as defined in claim 1, wherein card material is removed oversaid supported area while said card is in longitudinal motion.

3. A method as defined in claim 1, wherein the card material is removedover said supported area by abrading the card surface over said area.

4. A method as defined in claim 3, including the step of coating theabraded surface of the card with bonding material adapted to be utilizedsubsequently for bonding the microfilm in place.

5. A method as defined in claim 3, including the step of applying asolution of thermoplastic bonding material in a volatile solvent to saidabraded area.

6. A method of making record cards of fibrous material adapted to heapertured at predetermined locations for projectably mounting sectionsof microfilm and like projectable transparencies which comprises passingcards in succession first through an embossing zone and then through asecond zone in which material is removed from a side of the card,indenting the cards in said first zone on one side throughout a narrowelongated strip area extending around the outline of an aperture to beformed and thereby forming corresponding embossed projections on theother side, and then supporting said cards on said one side throughoutsaid embossed area as they pass through said second zone while removingsaid embossed projections from said other side.

7. A method as defined in claim 6, wherein the height of said supportfor said embossed area in said second zone is greater than the depth towhich said area was indented in said first zone.

8. A method as defined in claim 6, including the step of passing saidcards in succession through a third zone and therein coating the cardsurface from which said projections have been removed with bondingmaterial adapted to be utilized subsequently for bonding the film inplace.

9. A method as defined in claim 8, wherein a solution of thermoplasticbonding material in a volatile solvent is applied to said card surfacesfrom which said projections have been removed.

References Cited by the Examiner UNITED STATES PATENTS 2,667,822 2/54Christman 93-] 2,977,017 3/61 Herzig 93-1 X FRANK E. BAILEY, PrimaryExaminer.

BERNARD STICKNEY, Examiner.

1. A METHOD OF MAKING RECORD CARDS OF FIBROUS MATERIAL ADAPTED TO BEAPERTURED AT PREDETERMINED LOCATIONS FOR PROJECTABLY MOUNTING SECTIONSOF MICROFILM AND LIKE PROJECTABLE TRANSPARENCIES, COMPRISING THE STEPSOF EMBOSSING THE CARD BY INDICATING ONE SIDE THEREOF TO FORM A NARROWELONGATED TRENCH-LIKE AREA WHICH EXTENDS AROUND THE OUTLINE OF ANAPERTURE TO BE FORMED, THEREBY FORMING A CORRESPONDING PROJECTING AREAON THE OTHER SIDE OF THE CARD, AND THEN SUPPORTING SAID INDENTED AREAWHILE REMOVING THE PROJECTING MATERIAL FROM SAID OTHER SIDE OF SAID CARDTO A PREDETERMINED THICKNESS OVER SAID SUPPORTED AREA, THE REMAININGCARD AREA BEING UNSUPPORTED OUTSIDE SAID INDENTED AREA AND BEINGDEPRESSIBLE BELOW THE LEVEL OF SAID SUPPORT WHEREBY REMOVAL OF CARDMATERIAL IS LIMITED SUBSTANTIALLY TO SAID SUPPORTED AREA.